Active isothermal transport unit

ABSTRACT

A temperature control apparatus is provided. The apparatus comprises a temperature control device; an exoskeleton structure to house the temperature control device; and insulation disposed between the temperature control device and the exoskeleton structure; wherein the temperature control device is structurally integrated with the exoskeleton structure to define a monocoque.

PRIORITY

This application claims the benefit of priority to U.S. Provisional Patent Application No. 61/926,316 filed on Jan. 11, 2014, which application is incorporated herein by reference.

FIELD

Embodiments of the present invention relate to temperature control devices.

BACKGROUND

There are many cases in which there is a need for accurate temperature control. For example during the transportation of biological material there is a need to keep the temperature of said material within a very narrow temperature range.

SUMMARY

According to one aspect of the invention, there is provided an active isothermal transport unit for the transportation of any high-value item(s) that need precision temperature control during transit, regardless of exterior ambient environmental temperature. Advantageously, the active isothermal transport unit provides “temperature control in a box” and comprises unique materials and a construction that obviates the need for a protective shipping carton, as the unit itself provides more than sufficient strength to survive the rigorous and often abusive demands of shipping via carriers such as UPS and FedEx.

Advantageously, the active isothermal transport unit may be used to ship items such as biological specimens, pharmaceuticals, vaccines, semiconduction paste, metallurgical raw materials, etc.

The active isothermal transport unit provides a modern solution to the challenge of accurately and consistently shipping temperature-sensitive biological and/or pharmaceutical specimens or agents without the need for physical ice blocks, chemical heat packs, or large insulated EPS (Expanded Poly Styrene) boxes or other protective shipping containers. The active isothermal transport unit may be of a monocoque construction comprised of a robust exoskeleton and a proprietary system for insulation and structural support integrated with the exoskeleton

The active isothermal transport unit provides the ability to electronically regulate internal temperature in both positive (heating) and negative (cooling) capacities with regard to the specimens or agents being transported. Further, the active isothermal transport unit may be sensitive to outside ambient temperature conditions and self-adjusts to keep the specimens at the desired set point(s).

Other aspects of the invention will be apparent from the detailed description below.

BRIEF DESCRIPTION OF THE FIGURES

In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the invention. It will be apparent, however, to one skilled in the art that the invention can be practiced without these specific details. In other instances, structures and devices are shown in block diagram form only in order to avoid obscuring the invention.

The present invention, in accordance with one or more various embodiments, is described in detail with reference to the following figures. The drawings are provided for purposes of illustration only and merely depict exemplary embodiments of the invention. These drawings are provided to facilitate the reader's understanding of the invention and shall not be considered limiting of the breadth, scope, or applicability of the invention. It should be noted that for clarity and ease of illustration these drawings are not necessarily made to scale.

FIG. 1 shows a schematic drawing of an active isothermal transport unit 100 in accordance with one embodiment of the invention.

FIG. 2 shows a functional block diagram for the active isothermal transport unit 100, in accordance with one embodiment of the invention.

The figures are not intended to be exhaustive or to limit the invention to the precise form disclosed. It should be understood that the invention can be practiced with modification and alteration, and that the invention be limited only by the claims and the equivalents thereof.

WRITTEN DESCRIPTION

In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present technology. It will be apparent, however, to one skilled in the art that the present technology can be practiced without these specific details. In other instances, structures and devices are shown in block diagram form only in order to avoid obscuring the invention.

Reference in this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present technology. The appearance of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Moreover, various features are described which may be exhibited by some embodiments and not by others. Similarly, various requirements are described which may be requirements for some embodiments but not other embodiments.

Moreover, although the following description contains many specifics for the purposes of illustration, anyone skilled in the art will appreciate that many variations and/or alterations to said details are within the scope of the present technology. Similarly, although many of the features of the present technology are described in terms of each other, or in conjunction with each other, one skilled in the art will appreciate that many of these features can be provided independently of other features. Accordingly, this description of the present technology is set forth without any loss of generality to, and without imposing limitations upon, the present technology.

While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not of limitation. Likewise, the various diagrams may depict an example architectural or other configuration for the invention, which is done to aid in understanding the features and functionality that can be included in the invention. The invention is not restricted to the illustrated example architectures or configurations, but the desired features can be implemented using a variety of alternative architectures and configurations. Indeed, it will be apparent to one of skill in the art how alternative functional, logical or physical partitioning and configurations can be implemented to implement the desired features of the present invention. Also, a multitude of different constituent module names other than those depicted herein can be applied to the various partitions. Additionally, with regard to flow diagrams, operational descriptions and method claims, the order in which the steps are presented herein shall not mandate that various embodiments be implemented to perform the recited functionality in the same order unless the context dictates otherwise.

FIG. 1 shows a schematic drawing of an active isothermal transport unit 100 in accordance with one embodiment of the invention. Referring to FIG. 1, it will be seen that the unit 100 comprises a temperature control device 102 which is housed in a housing 104 which defines an exoskeleton-like structure. The device also comprises insulation 106 disposed between the temperature control device 102 and the housing 101, as will be described.

Turning now to FIG. 2 of the drawings, there is shown a functional block diagram for the active isothermal transport unit 100, in accordance with one embodiment of the invention. The unit 100 is shown to include the following components/functional blocks:

Electronic Control Means 200: In one embodiment, this may comprise a microprocessor-controlled unit capable of utilizing PID (Proportional Integral Derivative) reversing-polarity DC output and automatic tuning of same to (a) control power and polarity to a heat pump assembly 202, (b) read real time temperature data from a temperature sensor 206 via a temperature sensing means 208, receive commands from a user interface 210, and receive overheat data from a Peltier device 226 so that it may use PWM (Pulse-Width Modulation) to prevent such overheating by means of an overheating protection module 214. The block 200 may be firmware and/or software driven and hence may be customized to suit any range of temperature. Moreover the block 200 may be configured to support custom functionality the addition/removal of software. In one embodiment the electronic control means may comprise the model TEC1091 from Meerstetter Engineering GmbH of Switzerland.

Active Delta-T° device/heat pump assembly 202: In one embodiment, this may consist of a Peltier device heat pump 226 coupled to a heat sink 207. The assembly 202 may be solid state in nature and with no moving parts. Such devices are well-known and have been used in a range of devices from portable food coolers/heaters to laser temperature control.

Receptacle 204: This is a structure physically coupled with the heat pump assemble 202 and in one embodiment is comprised of a highly thermally-transmissive material such as 6063 aluminum alloy and maintains the ability to host a singular, or plurality of nested members. These may include, but are not limited to, test tubes, vials, straws, petri dishes, or other means of holding specimens. Latent heat of the specimens is actively extracted or infused, performed and maintained by the scope of this invention.

Temperature sensor 206: In one embodiment, this is comprised of a platinum 4-wire RTD (Resistance Temperature Detector), chosen for its ability to reliably and consistently report real time temperature data to electronic control means 202 through a temperature sensing module 208. However, it may also be a thermistor, thermocouple, diode string, or any electronic metrology device used to read temperature.

Temperature Sensing/Conversion means 208: This component may comprise means to interpret analog temperature signals from temperature sensor 206 and convert these data into digital format. The component 208 may be integrated into the component 200, in one embodiment.

Interface Means 210. This may comprise simple momentary-contact pushbuttons to set desired temperature set point for the receptacle 204 in increments. In one embodiment, it likewise may accept commands from a computer USB interface with regard to maintaining, or a subset or instructions, for ramping temperature between two or more set points over a period of time. The interface means 210 may contain means for logging temperature over a predetermined interval in predetermined read cycles (i.e. adjustable sampling rates from every minute to every 30 minutes) and transferring these data via USB to a computer, for validation and archiving of a particular transport cycle and the time vs. temperature data read from object/specimen in the receptacle 204.

Display 212. In one embodiment, this may comprise an OLED display, chosen for its extremely low power consumption and readability in both bright sun and dark conditions. The low power consumption is important to extend internal battery life during operation.

Overheating Protection Means 214. In one embodiment, this may comprise a simple fan 215 but with a ZERO RPM at ZERO PWM functionality. Owing to the nature of heat pump assembly 202 in one embodiment, it may be detrimental to power consumption and hence battery life by blowing ambient air onto item heat pump assembly 202 unless directed to do so by Peltier device 226 through the electronic control 200. The overheating protection means 214 in one embodiment only functions when directed to do so by the electronic control 200 through a signal from the Peltier device 226. In one embodiment, the overheating protection means may comprise an NTC-10K thermistor 217 configured to constantly monitor the temperature of the heatsink 207. Cooling fan 215 operates to cool the heat sink 207 under control of the electronic control 200.

Insulation and Structural Support 216: This component comprises a hybrid mixture of two densities of polyurethane foam. The foam may be that as supplied by Aeromarine Industries. In one embodiment, the foam density around the component 204 may be 2 lb per sq. ft, whereas the foam density around the heat pump assembly 202 may be 4 lb per sq ft. In one embodiment, the hybrid mixture expands to up to 30× its original volume, thus compression-fitting against all parts and filling every void. Advantageously, the 2 lb mixture has twice the R value of EPS foam (“Styrofoam”) so that 1 inch of 2 lb. density polyurethane equals 2 inches of Styrofoam. Further, the polyurethane is very strong and when formed, comprises a very sturdy encapsulating block which is relatively impervious to damage caused by shock or impact.

Exoskeleton 218: In one embodiment, this component is comprised of an off-the-shelf or custom-made or modified polypropylene exterior case, chosen for its near-indestructible nature, inability to crack or deform substantially upon impact, and can withstand being rolled over by a freight truck and impacting drops from various altitudes. Combined with the insulation and structural support 216 and anchoring means 224, the component 218 completes a “monocoque” construction technique wherein at minimum items 202, 204, 206, and 214 are integrated into the structural strength and shear force absorption of the exoskeleton 218. In one embodiment the exoskeleton may be defined by a Pelican Brand case comprised of polypropylene. A mixture of 3M 74 and 3M 90 adhesive sprays, may be used to make the polyurethane bond to the polypropylene. The monocoque design is well-known in aircraft, rockets, race cars and performance boats, etc. It derives its structural strength from its exoskeleton; transferring all shear and inertia-related trauma forces of the internal componentry to the exoskeleton which is extremely strong. In this manner, damage is avoided and the need for external padded boxes to ship the device is obviated. The non-necessity of a padded shipping carton eliminates a portion of the single largest expense a user will have during the lifetime use of a device such as this: overnight freight costs. These are based upon what carriers refer to as “dimensional weight” wherein a package that weighs perhaps 18 lbs. must be placed in a larger, padded box which is dimensionally-rated by the carrier as say 30 lbs. So the customer pays the 30 lb. price for shipping instead of the true 18 lb value. Advantageously, the active isothermal transport unit described herein eliminates this problem.

In one embodiment, the active isothermal transport unit 100 is fabricated such that there is secure bonding and attachment of components 202, 204, 206, 214, 218, and 210 by means of component 224 representing anchoring means.

Battery 220: In one embodiment, this component may comprise a rechargeable battery system of a nominal 18.5 volts @ 13 ampere-hours, of a type chosen for highest watt density per lb. to reduce weight.

AC mains to DC converter 222: In one embodiment, this component may be integrated into the exoskeleton 218 and has enough power (i.e. 70 watts) to be able to both charge battery and run system at the same time. This component may comprise a switch mode type DC supply, well-known and having the ability to accept mains voltage worldwide from 90-264 VAC.

Anchoring means 224: This component is used for anchoring items 202, 204, 214, and 218 at minimum. In one embodiment, this item(s) consist of 0¼-20 bolts with bent fender washers at 90° angles wherein they are captured and secured permanently by item 216 during the manufacturing process.

ON/OFF main power switch 228. In one embodiment, this component comprises a locking-type SPST toggle switch immune to accidental action in either direction. Thus, to operate the switch, action must be deliberate.

Anti-reverse current means 230. In one embodiment, a simple diode preventing battery drain backwards into DC supply when unit is switched off and no AC mains connected.

Physical Access Means 232. In one embodiment this component may comprise a rotating, screw-on disc lid allowing access to the receptacle 204 and securing the contents of same both via in-built EPS foam insulation layer at the underside of the disc, with a threaded rod located in its center point, followed by a polyethylene circular washer or gasket followed by a layer of compressible rubber foam. The compressible foam conforms to the nested member tops (i.e. test tubes) and remains stationary while the gasket allows the disc lid and EPS insulator to rotate around the threaded rod and allowing the disc to be screwed into place to cover the receptacle 204.

Additionally, the various embodiments set forth herein are described in terms of exemplary block diagrams, flow charts and other illustrations. As will become apparent to one of ordinary skill in the art after reading this document, the illustrated embodiments and their various alternatives can be implemented without confinement to the illustrated examples. For example, block diagrams and their accompanying description should not be construed as mandating a particular architecture or configuration. Also, techniques, devices, subsystems and methods described and illustrated in the various embodiments as discrete or separate may be combined or integrated with other systems, modules, techniques, or methods without departing from the scope of the present technology. Other items shown or discussed as directly coupled or communicating with each other may be coupled through some interface or device, such that the items may no longer be considered directly coupled with each other but may still be indirectly coupled and in communication, whether electrically, mechanically, or otherwise, with one another. Other examples of changes, substitutions, and alterations ascertainable by one skilled in the art, upon or subsequent to studying the exemplary embodiments disclosed herein, may be made without departing from the spirit and scope of the present technology.

Various embodiments of the present disclosure, as discussed above, may be practiced with steps and/or operations in a different order, and/or with hardware elements in configurations which are different than those which are disclosed. Therefore, although the technology has been described based upon these exemplary embodiments, it is noted that certain modifications, variations, and alternative constructions may be apparent and well within the spirit and scope of the technology. Although various exemplary embodiments of the present technology are described herein in a language specific to structural features and/or methodological acts, the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as exemplary forms of implementing the claims. 

1. Temperature control apparatus, comprising: a temperature control device; an exoskeleton structure to house the temperature control device; and insulation disposed between the temperature control device and the exoskeleton structure; wherein the temperature control device is structurally integrated with the exoskeleton structure to define a monocoque.
 2. The apparatus of claim 1, wherein the exoskeleton structure comprises polypropylene.
 3. The apparatus of claim 1, wherein the insulation comprises a polyurethane foam.
 4. The apparatus of claim 3, wherein the polyurethane foam comprises two parts.
 5. The apparatus of claim 4, wherein a first part comprises a foam density of 2 lb per sq.
 6. The apparatus of claim 5, wherein a first part comprises a foam density of 4 lb per sq.
 7. The apparatus of claim 4, wherein the first part at least partially encapsulates a receptacle of the temperature control device; the receptacle for receiving an object to be temperature controlled.
 8. The apparatus of claim 5, wherein the second part at least partially encapsulates a heat pump assembly of the temperature control device.
 9. The apparatus of claim 1, wherein the temperature control device comprises a single Peltier device.
 10. The apparatus of claim 2, wherein the polyurethane foam is bonded to the polypropylene exoskeleton. 